Method and means for treating fibrous materials



Feb. 26, 1935. F. SEIDEL ET AL 1,992,778

METHOD AND MEANS FOR TREATING FIBROUS MATERIALS Filgd Jan. 7, 1931 4 Sheets-Sheet 1 q /n venfor: m Zff;

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TREATMENT iii @HEMECAL kffiiZDaH- CAUQN G4 TEXTILES 5; WEEK? Feb. 26, 1935. F. SEIDEL ETQ'AL METHOD AND MEANS FOR TREATING FIBROUS MATERIALS FiledJan. 7, 1951 4 Sheets-Sheet 2 Feb. 26, 1935. F. SEIDEL ET AL METHOD AND MEANS FOR TREATING FIBROUS MATERIALS Filed Jan. 7, 1931 4 Sheets-Sheet 4 TREATMENT & CHEMICAL Fs'iQDlH- can Ii fit-it??? laws I ZIXTELES 62 R8533,

Patented Feb. 26, 1935 UNITE METHOD AND MEANS FOR TREATING FIBROUS MATERIALS Fritz Seidel, Berlin-Copenick, and Julian Ronke,

Langenbielau,

Germany,

assignors to firm Christian Dierig Aktiengesellschaft, Berlin- Grunau, Germany Application January 7, 1931, Serial No. 507,196 In Germany January 10, 1930 32 Claims.

This invention relates, broadly speaking to a method for treating fibrous materials for textile purposes and to means for carrying out this new method. It is particularly concerned with a method and with means for treating'such fibrous materials with al ternating el ectric current:

In a copending"application sunder Ser. No. 507,068, filed January 7, 1931 we have described a method of treating fibrous materials by means of alternating electric current. This copending application is particularly concerned with the application of high frequency current and medium frequency current. By further investigation of two of us it has been found that low frequency alternating current also exerts a very favorable influence on fibrous materials of the kind described, and that the use of low frequency current presents decided advantages from economical and other points of view.

It is an object of the present invention to provide a method for refining fibrous material for textile purposes of all kinds, such as loose fibre, yarn and fabrics, by the action of low frequency electric current.

It is a further object of this invention to promote the bleaching of fibrous material by passing an alternating low frequency electric current through the fibrous material, while the treatment takes place.

It is another object of the invention to describe a new method for refining fibrous material in which the removal of the sizing, the scouring, the bleaching and other steps of refinement are considerably accelerated by simultaneous application of an alternating low frequency current.

A further object of the invention consists in leading a low frequency current through moist fibrous materials outside of a liquid bath.

Another object of the invention consists in the refining of fabrics by subjecting them once or several times to a process which includes the steps of saturating the fabrics with a solution of a chemical; of then passing an alternating low frequency current through the saturated fabrics, and of then washing, steeping in dilute acid, and again washing the fabrics.

A further object of the invention is to moisten such fibrous materials with a solution bf a suitable chemical to which have been ad ed compounds which decrease the rate of chei ical reaction between the fabric and the chemical in solution, and colloids for the absorption of pectins. proteins and coloring matters; and to lead a low frequency current through the thus moi tend material.

It is a further object of the invention to remove or decompose the sizing from, to scour or degrease, and to bleach textile fabrics simultaneously in one operation by passing the fabrics first through a bath containing desizing, scouring and bleaching compounds and by then leading a low frequency electric current through the material.

A further object of the invention consists in a device for leading a low frequency alternating current through fibrous textile material.

It is another object of the invention to provide electric contacts along the path of a fabric, these contacts being spaced from each other, and subsequent contacts being connected to different terminals of a source of low frequency current.

Still another object of the invention consists in a device containing a plurality of spaced metallic rollers which are supplied with alternating electric current and over which the fibrous material is guided; and means for moistening the fibrous material.

Other objects of the new method and the new means for carrying out the method will be more clearly understood by the following detailed description, partly with reference to the appended drawings. It should be pointed out, however, that the device shown in the drawings is only described by way of an example and that the invention should not be limited to the specific details of this example, either for the part of this invention which relates to the method, or for the part relating to the means for carrying out the new method, as many modifications will easily present themselves to anybody skilled in the art.

In carrying out the new method, a low frequency electric current is led through the fibrous material so that the fibrous material itself forms part of the electric circuit, the alternating current passing through and being conducted by the fibrous material. To make the fibrous material conductive, it should contain moisture, and if the fibrous material itself does not contain enough moisture for enabling it to conduct the electric current, then the material should be moistened before applying the current. Water may be used as a moistening agent, and it has been found that the application of the alternating current to textile fabrics moistened with water alone causes a remarkable bleach ingoithe material. In a preferred foriifof this invention, howeverr solutions of chemicals are used as moistening agents, such as bleaching liquids containing chlori or oxygen, liquids for decomposingthe si z i iig,v the EE CaIieH buckS or scouring liquors, etc. Solutions of these kinds are well known in the art of refining fibrous material. The liquids used in the new method are similar to the hitherto used liquids, as far as the general composition is concerned. The bleaching action therefore is not primarily an effect of electrolysis, as may be derived from a direct current, used in the old method, but rather analogous to that induced by a catalyst, the alternating current serving to loosen the molecular structure of the bleaching agents andthe latter effecting the bleaching in a purely chemical way.

While it is possible to lead the low frequency current through the fibrous material, while the material is immersed in a liquid bath, the preferred form of the new method consists in leadmi alfdws ai dfitifimment of the mateial and gives very uniform results; it further results in very considerable saving of chemicals. The method will now be described in a preferred form in application to textile fabrics. he textile fabric is firstmoistened with aggluhorrors"suitatieeii'afiiai, pre f'rabl'y compositions which will be described in a later part of this specification. The textile fabric is then ed to a series of metallic members which are connected to the alternating current supply. While passing over these members the" textile fabric can be again sprinkled with the chemical solution or it can be led through a container filled with a solution of a chemical afterhaving passed over some of the contact members and the fabric is then passed over the rest of the members. This cycle of operation can be performed several times as will be still nearer explained.

Voltage up to about 220 volts and strength of current up to 75 amperes have been found to give good results. The current had a frequency of about 50/60 complete alternations per second. It should be said, however, that these figures have to be only regarded as a clue and that low frequency alternating currents of other frequencies may be also used with success. It is a decided advantage of the present method that it can be performed by using the usual commercial alternating current for lighting of about 220 or 250 volts, which is readily available in most plants. Although current of this type has a relatively low frequency, said frequency is high enough to prevent electrolysis.

To give a distinct definition it might be mentioned, that the term low frequency current is used in this specification and in the claims for currents the number of alternations of which is less than 500 alternations per second.

The solutions of chemicals used in the present process should as a rule have much higher concentration of the chemical constituents than ordinary bleaching liquids and the like. Therefore special care has to be taken to prevent destruction of the fibres by the highly concentrated chemicals and to prevent the initial formationof the detrimental oxy-compounds (Oxy- -Verbindungen). This formation is prevented by properly adjusting in every special case the rate of the bleaching reaction and of the other chemical reactions, by adding anti-catalyzers. Suitable anti-catalyzers are for example: magnesium silicate in colloid form for bleaching liquids containing oxygen; a solution of caustic soda for bleaching liquors containing hypochlorite; sulphuric acid for bleaching liquors containing sodium peroxide.

It is further advisable to add to the different baths, colloids for absorbing the pectins, protein substances and coloring matters which are liberated by the various reactions. Amongst the colloids, waste lyes of the sulphite cellulose process, and water glass may be used.

By adding electrolytes or non-electrolytes to the baths the electric conductivity of the saturated fibrous material may be influenced in a way to yield in each case the most favorable electric conductivity.

By the new method it is possible to decrease the duration of the different refining treatments to a small fraction of the hitherto necessary time. For instance, the refining of cotton fabric, which up to now takes about 48 hours, can be carried out with the new method in less than /2 hour.

It is possible with the new method to remove fully the sizing or dressing from the fabric and to scour (beuchen) and to bleach the fabric to a perfect white within this short time. It is clear that this speeding up of the procedure presents high advantages. It is further possible with the new method to carry through the whole treatment in form of a continuous process.

The new method can be used for each separate step of refinement, such as the decomposing of the sizing; the removing of the cotton wax, the bleaching etc. It has been found, that these different steps can also be combined.

It is also possible to carry out only one of the steps with the aid of an alternating low frequency current. For instance, the washing out of the dressing or sizing can be performed in the well known process by means of diastase, should this be desirable. Then only the scouring and bleaching would be carried out under action of the alternating current. Or the material may be also still scoured in the old way and then only bleached under action of the alternating current.

In most cases it will be advisable to promote the whole refinement by the application of the alternating current.

In the following, two examples are given for the treatment of cotton fabrics, one for a treatment containing three subsequent steps and the second for a treatment containing one single process, both of the treatments resulting in the complete refining of the raw fabric into white cotton.

Example I.A low frequency current of about 160 volts and 75 amperes is led through cotton fabric which had been previously moistened with a strongly alkaline solution of hypochlorite, to which are added preservative colloids, anti-catalyzers and a moistening agent. After the material has been submitted to the action of the alternating current for four minutes, it is passed into a washing bath, then into a bath of dilute acid and into a second washing bath.

The material is then passed through a bath of stabilized alkaline peroxide to which it may be advisable to add small quantities of an electrolyte, for instance, sodium-sulphate, and the material is then again submitted for about three minutes to the action of an alternating current of about 220 volts and of 42 amperes. In addition to this treatment the material is again washed and treated with dilute acid.

This second step of the treatment is followed by a third electrical treatment previous to which the fabric is impregnated with a solution of hypo- Cal chlorite of the same general kind as the first employed solution, the second solution being less concentrated. The low frequency current is led through the fabric for about four minutes. This treatment is followed again by the usual steps of washing, of immersing in dilute acid and of again washing.

The material is then completely bleached, and also the sizing or dressing is also fully removed, and the scouring is completed.

The solution applied to the fabric previous to the first electrical treatment may contain per liter:

5 g. active chlorine 8 g. sodium hydroxide 0.5 ccm. of a moistening agent 25 g. sodium chloride.

The second step of the process may be started by moistening the material with a solution containing per liter:

10 g. calcined soda 15 g. sodium hydroxide 0.5 ccm. water glass 0.5 ccm. of a waste lye of the sulphite cellulose process 0.5 ccm. of an emulsion of dipentene 25 g. sodium sulphate The solution used in the third phase of treatment may contain per liter:

4 g. active chlorine 10 g. sodium hydroxide 30 g. sodium sulphate Example II .-The textile fabric is immersed in a bath containing per liter the following compounds:

8 g. active chlorine 30 g. sodium hydroxide 5 com. emulsion of dipentene 20 g. sodium sulphate 50 com. waste lye of the sulphite cellulose process 0.5 ccm. water i 0.5 ccm. of a moistening agent In this solution the chlorine acts as a bleaching means and also as a means for decomposing the starch contained in the sizing. The solution of sodium hydroxide, too, acts as a means for decomposing the starch and furthermore acts as an anti-catalyzer or stabilizing means for the hypochlorite solution. The emulsion of dipentene dissolves the fatty compounds of the socalled cotton waxes. The sodium sulphate increases the electric conductivity and the sulphite waste lye as well as the water glass serve as colloids for absorbing impurities and decomposition products of the reactions of the liquor with the fibrous material.

By leading a low frequency current through the fabrics which had been previously immerged in the described liquid, washing out or decomposing of the dressing, scouring and bleaching reactions are simultaneously initiated.

For carrying out the new method a device has to be used by which alternating low frequency current can be led through the fibrous material. This device consists in its most important part of one or more pairs of metallic members, which contact with the fibrous material and in which each of the two members of each pair is connected to one of the poles of an alternating low frequency supply. The two members of each pair may be located opposite each other, and the fibrous material will be located between these members, contacting with each of them. If the fibrous material which is to be treatedfis in the form of long strips of fabric or long bundles of yarn, a preferred device comprises members which are arranged along the path of movement of the fibrous material and spaced from each other, whereby the alternating current passes, not vertically through the strips, but is conducted along the strips. The shape of the contact members depends from the specific circumstances of each single case. Plates, rollers and other forms may be used.

Referring now to the drawings:

Fig. 1 shows diagrammatically in elevation a device for carrying out the new method.

Fig. 2 is a plan view of the device shown in Fig. 1.

Fig. 3 shows diagrammatically the arrangement of alternating current devices for a working cycle which contains three subsequentsteps.

Figs. 4 to 7 are examples of wiring diagrams for the alternating current apparatus shown in Fig. 1.

The device consists of a container A, of the,

alternating current machine B, of a second liquorv container C, of washing'devices D and F and.- of an acid container E, in which acid is contained. In machine B 9, 12 designates a frame, each branch of which carries insulated supports for a plurality of contact rollers connected to the terminals of the source of alternating current. The frame is insulated from the rollers in any suitable manner. The rollers 7af and 8af are located within frame 9 and the rollers 1311-1 and l4af are located within frame 12. A series of distributing rollers 10 are supported by bearing 11 located in the upper part of themachine between the two parts of the frame. The distributing rollers are insulated and each of them may have a metallic core, coated with ebonite. Driving rollers 15 are provided at the lower part of the machine.

The contact rollers preferably consist of aluminium and are so connected to an alternatin current supply that a voltage difference exists between subsequent rollers, thus ensuring the flowing of alternating current along the whole length of the fabric.

In Fig. 1 the electrical connections are diagrammatically shown. The rollers 7a to f are connected to a branch 36, and the rollers 14a to f are connected to a branch 37. branches are connected to terminal 44 of an alternator or other alternating current supply 43. In the same manner rollers 8a to ,f are connected to a branch 39 and roller 13a to f to a branch 38, where both branches meet at the second terminal 42 of the alternating current supply 43.

The washing machines D and F consist each of a container filled with a suitable washing solution and each machine contains a series of guide rollers. Device E consists of an acid proof vessel and contains also suitable guiding rollers. The fabric 1 is first guided by means of rollers 2, 3, 4 and 5 through container A filled with a suitable liquid and is then led into the alternating current machine B. The fabric passes over the sets 7a) and Sa-f of contact rollers to the uppermost of the distributing rollers 10 and is then led into and through the container C by means of guiding rollers 18, 19 and 20. This container, too, is filled with the same liquid as container A. The fabric then enters the second series of contact rollers 13a-- and 14a-f and is guided downwardly. It leaves this part of the apparatus passing over guiding roller 16, and between driving rollers 15 and enters again the Both of these left part of the alternating current machine over guiding roller 17. The fabric takes then the same way and is fed from contact roller 8 to the second of the distributing rollers 10 as clearly shown in the drawings. Without passing through container C it is directly guided downwardly. This cycle is passed a plurality of times, after which the fabric is led for a second number of cycles only upward to roller 8c in the left part of the apparatus and down over roller 14c. In the last series of cycles the fabric reaches the contact rollers 8d and 1411 only.

It is apparent that a plurality of layers of material will thus constantly pass between the electrically conducting contact rollers. In the drawings 15 layers have been designated but it is as well possible to drive with fewer or with considerably more layers. It has been found advisable in practice to have a series of 50 layers passing simultaneously between the contact rollers.

As shown in the drawings, additional contact rollers engage opposite sides of the assembly of fabric layers. This is important, because this arrangement ensures that the alternating current passes through all of the layers and not merely along a few of the outer layers as would be the case if the subsequent contact rollers would engage one and the same side of the assembly.

The fabric passes out of machine B over rod 21 which is secured in an inclined direction, preferably at an angle of 45 degrees and which allows the fabric to leave machine B in a direction forming a right angle with the direction in which the fabric entered machine B.

As shown in Fig. 2 a second inclined rod 22 may be provided for once more deflecting the direction of movement of the fabric, whereby the fabric regains its initial direction of movement. The fabric passes then between squeezing rollers 23 and is led through the washing machine D, acid container E and washing machine F. Suitable compensating devices G and H may be inserted between the different parts of the machinery for compensating the tension of the material, and additional squeezing rollers may be provided at the outlet of each of the machines D, E and F for removing the excess of fluid. As this latter part of the machinery is well known in the art, no detailed description of it is deemed necessary.

Fig. 3 is a diagrammatic general view of a preferred disposition of the different parts of a device for carrying out processes of the kind described in above Example 1. The fabric passes into the machine at a and is first led through bath A. The electrical devices B, B, B" are positioned at right angles to the washing devices D, D, D compared with the position shown in Figs. 1 and 2, whereby the fabric can be led to the washing devices without needing to be deflected by a second inclined rod, such as rod 22 of Fig. 2. E, E, E" designate the acid devices and F, F, F the second washing devices.

It is apparent from Fig. 3 that it is possible to lodge the whole machinery in comparatively small space.

Figs. 4 to 8 are electric wiring diagrams for the contact rollers.

Fig. 4 shows subsequent rollers alternatingly connected to one of two different electrical poles I, II of the alternating current supply 40. Taking the case of the usual 220 volt-current for lighting, this way of connecting would result in difference of voltage of 220 volts between each pair of subsequent rollers. The reference numbers of the rollers in this figure as well as in Figs. 5 to 8 correspond to the numbers used in Fig. 1.

Fig. 5 shows a combination between two phases I, II of the alternating current and earth J.

In Fig. 6 three phases I, II, III of an alternating three-phase alternating current machine 41 and earth J are combined, while Fig. '7 shows the combination between one phase I and earth J. The differences of voltage between subsequent rollers in the arrangements of Figs. 5 to 7 vary between 220 volts and 110 volts.

The alternating low frequency current can be used for refining fibrous material of all kind, such as vegetable fibres, animal fibres or artificial fibres, for instance, artificial silk. It is applicable to the fibrous material in any state of manufacture. Loose fibre, yarn and fabrics can be treated in the described way. As hereintofore stated the new treatment results in a very considerable decrease of duration of the different refinement steps. It is further made possible to perform the whole treatment as a continuous process.

Having shown and described the invention in its aspects and details, what is claimed is particularly pointed out in the following claims.

We claim:

1. A method for treating textile material which contains an absorbed liquid adapted to react with the same, under the influence of an alternating electric current whose frequency is sufficiently high to prevent and electrolysis of said liquid which consists in passing an alternating current through said material, the frequency of said alternating current being not greater than 500 cycles per second, said frequency being sufficiently high to prevent any electrolysis of said liquid, said liquid being a conductor of electricity.

2. A method of treating textile material which contains an absorbed liquid adapted to react with the same, which consists in passing through said fibrous material a three-phase alternating current whose frequency is not greater than 500 cycles per second.

3. A method of treating textile material which comprises the step of guiding said material through a bath containing a liquid adapted to be absorbed by said material and to react with the same; and of passing through said fibrous material a three-phase alternating current whose frequency is not greater than 500 cycles per second, when said material has left the liquid bath.

4. A method of treating textile material which contains an absorbed liquid adapted to react with the same, which consists in passing through said fibrous material a three-phase alternating current whose frequency is not greater than cycles per second, the voltage of said current being that of the usual lighting current.

5. A method of treating textile material which consists in subjecting said material to the action of an alternating electric current of not more than 500 cycles per second, while said fibrous material contains an electrolyte which is adapted to react with said material under the influence of said current, the frequency of said current being sufficiently high to prevent any electrolysis of said electrolyte.

6. A method of treating fibrous material which consists in subjecting said material to the action of an alternating electric current, while said fibrous material contains a mixture of an electrolyte with a non-electrolyte in order to regu- Nit Carissa Search late the conductivity of the absorbed liquid, the frequency of said alternating electric current being not greater than substantially 500 cycles per second.

'7. A method of treating fibrous material which consists in subjecting the same to the action of an alternating current, while said material contains an absorbed liquid adapted to react with said fibrous material, said absorbed liquid including an anti-catalyzer, the frequency of said alternating electric current being not greater than substantially 500 cycles per second.

8. A method of treating fibrous material which consists in subjecting the same to the action of an alternating current, while said material contains an absorbed liquid adapted to react with said fibrous material, said liquid including a colloid which can adsorb an ingredient of said fibrous material, the frequency of said alternating electric current being not greater than substantially 500 cycles per second.

9. A method of treating fibrous material which consists in subjecting the same to the action of an alternating current, while said material contains an absorbed liquid adapted to react with said fibrous material, said liquid including a colloid which can adsorb an ingredient of said fibrous material, said colloid being adapted to adsorb pectins, proteins and coloring material which is present in said fibrous material, the frequency of said alternating electric current being not greater than substantially 500 cycles per second.

10. A method of treating textile material which contains an absorbed conducting liquid adapted to react with the same under the influence of an alternating current,whosefrequencyissufiicientlw higr ..to., p, :ylentlanyaelerarnlysianihsa liquid, which consists in passing said fibrousmaterial over rollers which contact with opposite faces of said fibrous material, while sending an alternating current to said rollers, said current having a frequency which is sufiiciently high to prevent any electrolysis of said liquids.

11. A method of treating textile material containing an absorbed conducting liquid which reacts with said material under the influence of an alternating current whose frequency is sufiiciently high to prevent any electrolysis of said liquid, which consists in subjecting the said material to the action of an alternating electric current in a series of stages, said alternating current having a frequency which is not greater than 500 cycles per second and which is sufiiciently great to prevent any electrolysis of said liquid, and moistening said fibrous material between said stages.

12. A method of treating textile material containing an absorbed conducting liquid which reacts with said material under the influence of an alternating current whose frequency is sufliciently high to prevent any electrolysis of said liquid, which consists in subjecting the said material to the action of an alternating, electric current in a series of stages, said alternating current having a frequency which is not greater than 500 cycles per second and which is sufficiently great to prevent any electrolysis of said liquid, and moistening and washing said fibrous material between said stages.

13. A method of treating textile material containing an absorbing conducting liquid which reacts with said material under the influence of an alternating current whose frequency is sufi'iciently high to prevent any electrolysis of said liquid, which consists in subjecting the said material to the action of an alternating electric current in a series of stages, said alternating current having a frequency which is not greater than 500 cycles per second and which is sufiiciently high to prevent any electrolysis of said liquid, and moistening and washing said fibrous material between said stages, the fibrous material being continuously moved from stage to stage during the whole treatment.

14. Apparatus for treating textile material which contains an absorbed liquid, comprising a series of rollers which are spaced from each other along the path of movement of said material and over which said fibrous material is passed so that said rollers contact with opposite faces of said fibrous material, succeeding rollers being connected to opposite terminals of a source of alternating current.

15. Apparatus for treating textile material which contains an absorbed liquid, comprising a plurality of rollers which are spaced from each other along the path of movement of said material and over which said fibrous material is passed so that said rollers contact with opposite faces of said fibrous material, succeeding rollers being connected to opposite terminals of a source of alternating current, said rollers being arranged in separated series, a receptacle containing a liquid and located between said series, and means adapted to guide said fibrous material through said receptacle intermediate said series.

16. A method of treating textile material which consists in leading through said material an alternating electric current of less than 500 cycles per second, while said textile material contains a mixture of an electrolyte with a non-electrolyte in order to regulate the conductivity of the absorbed liquid.

17. A method of treating textile material which consists in leading through said material an alternating current of less than 500 cycles per second, while said material contains an absorbed liquid adapted to react with said textile material, said absorbed liquid including an anti-catalyzer.

18. A method of treating textile material which consists in leading through said material an alternating current of less than 500 cycles per second, while said material contains an absorbed liquid adapted to react with said textile material, said liquid including a colloid which can adsorb an ingredient of said textile material.

19. A method of treating textile material containing an absorbed liquid, which consists in leading through said material an alternating electric current in a series of stages, said alternating current having a frequency which is not greater than 100 cycles per second; and moistening and wash-, ing said textile material between said stages, the

textile material being continuously moved from stage to stage during the whole treatment.

20. Method of continuously treating textile material which comprises advancing the material along a path in a series of stages, while passing an alternating current through and along said material; and passing the said material through baths of suitable liquids between said stages, the frequency of said alternating electric current being not greater than substantially 500 cycles per second.

21. Apparatus for treating textile material comprising means for guiding said material along substantially vertical paths; two series of rollers connected to opposite terminals of a source of alternating current; each of the said series containing a plurality of rollers spaced from each other along the said paths; the rollers of the one series contacting with one surface of the said material, and the rollers of the other series contacting with the opposite surface of said material, the rollers of the one series being located along the said paths in the free spaces between subsequent rollers of the other series.

22. A method for treating textile material under the influence of an alternating electric current whose frequency is sufficiently high to prevent any electrolysis of said liquid which contains an absorbed liquid which is adapted to react with said textile material, which consists in passing through the moistened textile material an alternating current whose frequency does not exceed 500 cycles per second, the frequency of said current being sufficiently high to prevent said electrolysis the path of said current being limited to the moistened textile material by causing said textile material which is traversed by the current to be free from contact with any external body of said liquid.

23. A method for treating textile material under the influence of an alternating electric current whose frequency is sufliciently high to prevent any electrolysis of said liquid which contains an absorbed electrolyte which is adapted to react with said textile material, which consists in passing through the moistened textile material an alternating current whose frequency does not exceed 500 cycles per second, the frequency of said current being sufliciently high to prevent said electrolysis the path of said current being limited to the moistened textile material by causing said textile material to be free from contact with any external body of said electrolyte.

24. A method of treating fibrous material which consists in subjecting the same to the action of an alternating current, while said material contains an absorbed liquid adapted to react with said fibrous material, said liquid including a colloid which can adsorb an ingredient of said fibrous material, said colloid being adapted to adsorb pectins, proteins and coloring material which is present in said fibrous material, the path of said current being limited to the moistened material by causing said material to be free from contact with any external body of said liquid.

25. A method of treating textile material which consists in leading through said material an alternating electric current of less than 500 cycles per second, while said textile material contains a mixture of an electrolyte with a non-electrolyte in order to regulate the conductivity of the absorbed liquid, the path of said current being limited to said moistened material by causing the material which is traversed by the current to be free from contact with any external body of said mixture.

26. A method of treating textile material which consists in leading through said material an alternating current of less than 500 cycles per second, while said material contains an absorbed liquid adapted to react with said textile material, said absorbed liquid including an anti-catalyst, the path of said current being limited to the moistened material by causing the material which is traversed by the current to be free from contact with any external body of said liquid.

27. A method of treating textile material which consists in leading through said material an alternating current of less than 500 cycles per second, while said material contains an absorbed liquid adapted to react with said textile material, said liquid including a colloid which can adsorb an ingredient of said textile material, the path of said current being limited to the moistened material by causing said material to be free from contact with any external body of said liquid.

28. A method of continuously treating cotton material which comprises advancing the material along a path in a series of stages, while passing an alternating current through and along said material; and passing the said material through baths of suitable liquids between said stages; said liquids reacting with said material under the infiuence of said alternating current to desize and scour and bleach said material, said current having a frequency which is sufficiently high to prevent any electrolysis of said liquids, whereby the sizing is removed from said material, and the said material scoured and bleachedinone continuous process. 7

29. A method of continuously treating cotton material which comprises advancing the material along a path in a series of stages, while passing an alternating current through and along said material, and passing the said material through baths of suitable liquids between said stages, said liquids reacting with said material under the influence of said alternating current to desize and scour and bleach said material, said current having a frequency which is sufficiently high to prevent any electrolysis of said liquids the electrical part of the treatment taking not more than half an hour, whereby the sizing is removed from said material, and the said material scoured and bleached in one continuous process.

30. A method of treating fibrous material in web form and which contains a conducting liquid which reacts with said material under the influence of an alternating electric current whose frequency is sumciently high to prevent any electrolyisis of said liquid, which consists in causing an alternating current having such high frequency to pass along and through a part of the length of said web.

31. A method of treating fibrous material in web form and which contains a conducting liquid which reacts with said material under the influence of an alternating electric current whose frequency is sufiiciently high to prevent any electrolysis of said liquid, which consists in causing an alternating current having such high frequency to pass along and through a part of the length of said web, said alternating current being led to and away from said web at opposite faces of said web.

32. A method of treating fibrous material which is in the form of a plurality of superposed web layers and which contains a conductive liquid which reacts with said material under the influence of an alternating electric current whose frequency is sufficiently high to prevent any electrolysis of said liquid, which consists in causing an alternating current having such high frequency to pass along and through a part of the lengths of all said webs.

FRITZ SEIDEL. JULIAN RONKE. 

